One of my favorite scenes from the silly-yet-clever (and maybe wise, in places) movie The Adventures of Buckaroo Banzai Across the 8th Dimension occurs when Buckaroo and his colleague New Jersey are chatting in the midst of performing brain surgery:

NEW JERSEY: "See, this is the part, where for me, it started to look like a problem. You know, I wanted to sacrifice the precentral vein in order to get some exposure, but because of this guy's normal variation, I got excited, and all of a sudden I didn't know whether I was looking at the precentral vein, or one of the internal cerebral veins, or the vein of Galen, or the basal vein of Rosenthal. So, on my own, me, at this point, I was ready to say that's it, let's get out."

BUCKAROO BANZAI: "You can check your anatomy all you want, and even though there may be normal variation, when you get right down to it, this far inside the head it all looks the same. No, no, no, no, no. Don't tug on that! You never know what it might be attached to."